杨明;许丽英;宋雨;王新;贾永锋;

• 1:中国科学院沈阳应用生态研究所中国科学院污染生态与环境工程重点实验室

摘要(Abstract)：

厌氧微生物作用下土壤中砷的形态转化及分配比例对砷的环境行为与归趋具有重要影响。实验利用张士污灌区土壤负载低浓度砷,研究了厌氧微生物作用下砷的形态转化过程,并通过磷酸盐及盐酸提取土壤中的砷、铁和硫,探讨了砷在土壤中结合形态的变化及土壤矿物结构转化与砷环境行为的关联。实验结果表明,微生物作用下土壤负载的砷被迅速还原为As(III)并释放进入液相,培养24h后液相累积的As(T)量达到16.9μmol·L-1,其中As(III)占液相总砷含量的91%以上;48h后释放的砷被再次固持,液相残留的As(III)浓度仅为1.5μmol·L-1。尽管微生物还原作用造成土壤中铁氧化物的活化,但固相中磷酸盐提取态与盐酸提取态砷所占的比例分别从载砷量的45.3%和49.8%降低到22.0%与0.22%,而体系中硫酸盐还原产生的硫离子的量与砷的释放量保持负相关。可见微生物还原作用下砷发生了活化,释放和再固定的过程,土壤负载的砷从溶解态、吸附态及铁氧化物结合态逐渐被转化为更稳定的硫化物结合态。此研究对于预测土壤中砷的行为与归趋及污染土壤修复具有一定意义。

关键词(KeyWords)： 土壤;砷;微生物还原;形态转化;再分配

Abstract:

Keywords:

基金项目(Foundation): 国家杰出青年科学基金(40925011);; 国家自然科学基金(41273133)

作者(Author): 杨明;许丽英;宋雨;王新;贾永锋;

Email:

参考文献(References)：

• [1]Liu H Y,Probst A,Liao B H.Metal contamination of soils and crops affected by the Chenzhou lead/zinc mine spill(Hunan,China)[J].Science of the Total Environ-ment,2005,339(1-3):153—166
• [2]肖细元,陈同斌,廖晓勇,等.中国主要含砷矿产资源的区域分布与砷污染问题[J].地理研究,2008,27(1):207—208Xiao X Y,Chen T B,Liao X Y,et al.Regional distribu-tion of arsenic contained minerals and arsenic pollution in China[J].Geographical Research,2008,27(1):207—208(in Chinese)
• [3]Vincent C,Remy B,Florence S,et al.Effect of indige-nous bacterial activity on arsenic mobilization under an-aerobic conditions[J].Environment International,2005,31(2):221—226
• [4]Islam F S,Gault A G,Boothman C,et al.Role of met-al-reducing bacteria in arsenic release from Bengal delta sediments[J].Nature,2004,430(6995):68—71
• [5]Kocar B D,Borch T,Fendorf S.Arsenic repartitioning during biogenic sulfidization and transformation of fer-rihydrite[J].Geochimica et Cosmochimica Acta,2010,74(3):980—994
• [6]Pedersen H D,Postma D,Jakobsen R.Release of arse-nic associated with the reduction and transformation of iron oxides[J].Geochimica et Cosmochimica Acta,2006,70(16):4116—4129
• [7]Wang S,Xu L,Zhao Z,et al.Arsenic retention and re-mobilization in muddy sediments with high iron and sul-fur contents from a heavily contaminated estuary in China[J].Chemical Geology,2012,314—317:57—65
• [8]Kneebone P E,O'Day P A,Jones N,et al.Deposition and fate of arsenic in iron and arsenic enriched re-servior sediments[J].Environmental Science&Tech-nology,2002,36(3):381—386
• [9]Lee J,Lee S,Chon H,et al.Enhancement of arsenic mobility by indigenous bacteria from mine tailings as response to organic supply[J].Environment Interna-tional,2009,35(3):496—501
• [10]Samantha L S,Benjamin C B.Changes in iron,sulfur,and arsenic speciation associated with bacterial sulfate reduction in ferrihydrite-rich systems[J].Environmen-tal Science&Technology,2009,43(23):8787—8793
• [11]Barringer J L,Mumford A,Young L Y,et al.Pathways for arsenic from sediments to groundwater to steams:Biogeochemical processes in the Inner Coastal Plain,New Jersey,USA[J].Water Research,2010,44(19):5532—5544
• [12]Bostick B C,Fendorf S.Arsenic sorption on troilite(FeS)and pyrite(FeS2)[J].Geochimica et Cosmochimi-ca Acta,2003,67(5):909—921
• [13]Jonsson J,Sherman D M.Sorption of As(III)and As(V)to siderite,greenrust and magnetite:Implications for arsenic release in anoxic groundwaters[J].Chemical Geology,2008,255(2):173—181
• [14]Keon N E,Swartz C H,Brabander D J,et al.Validation of an arsenic sequential extraction method for evalua-ting mobility in sediments[J].Environmental Science&Technology,2001,35(16):2778—2784
• [15]Zhang X,Jia Y,Wang S,et al.Bacterial reduction and release of adsorbed arsenate on Fe(III)-,Al-and co-precipitated Fe(III)/Al-hydroxides[J].Journal of Envi-ronmental Sciences,2012,24(3):440—448
• [16]石荣,贾永峰,王承智,等.溶解性有机酸对砷在土壤矿物质表面吸附-解吸行为的影响[J].土壤通报,2009,40(4):761—766Shi R,Jia Y F,Wang C Z,et al.Effect of dissolved or-ganic acids on arsenate adsorption-desorption onto soil mineral[J].Chinese Journal of Soil Science,2009,40(4):761—766(in Chinese)
• [17]Polizzotto M L,Harvey G F,Li G,et al.Solid-phases and desorption processes of arsenic within Bangladesh sediment[J].Chemical Geology,2006,228(13):97—111
• [18]Islam F S,Pederick R L,Gault A G,et al.Interactions between the Fe(III)-reducing bacterium Geobacter sul-furreducens and arsenate,and capture of the metalloid by biogenic Fe(II)[J].Applied and Environmental Mi-crobiology,2005,71(12):8642—8648
• [19]Pérez-Jiméneza J R,DeFraia C,Young L Y.Arsenate respiratory reductase gene(arrA)for Desulfosporosinus sp.strain Y5[J].Biochemical and Biophysical Research Communications,2005,338(2):825—829
• [20]Oremland R S,Stolz J F.The ecology of arsenic[J].Science,2003,300(5621):939—944
• [21]Smedley P L,Kinniburgh D G.A review of the source,behaviour and distribution of arsenic in natural waters[J].Applied Geochemistry,2003,17(5):517—568
• [22]北京师范大学、华中师范大学、南京师范大学的无机化学教研室.无机化学上册[M].第四版.北京:高等教育出版社,2002:419—420
• [23]Kirk M F,Roden E E,Crossey L J.Experimental anal-ysis of arsenic precipitation during microbial sulfate and iron reduction in model aquifer sediment reactors[J].Geochimica et Cosmochimica Acta,2010,74(9):2538—2555
• [24]O'Day P A,Vlassopoulos D,Root R,et al.The influ-ence of sulfur and iron on dissolved arsenic concentra-tions in the shallow subsurface under changing redox conditions[J].Proceedings of the National Academy of Sciences of the United States of America,2004,101(38):13703—13708
• [25]Xu L,Zhao Z,Wang S,et al.Transformation of arse-nic in offshore sediment under the impact of anaerobic microbial activities:An in-vitro investigation[J].Wa-ter Research,2011,45(20):6781—6788